Can testing device



Patented Jan. 25, 1938 v "UNITED STATES PATENT OFFICE CAN 'rns'rmo DEVICE Guy P. Hensley, Gustine, Calif. Application November 5, 1934, Serial No. 751,632

' 3 Claims. (01. 73-51 My invention relates to a can testing device,

and particularly to those which are adapted to test cans with the top covers permanently secured to the body of the can and having 'a'cen- 5 trally disposed vent hole in the top cover. through which the cans are filled with fiuid such as milk, oil, tomato juice, and the like.

An object ofmy invention is to provide automatic means for testing sealed cans and for segregating the unsealed cans from sealed cans.

Other objects and advantages will appear in the following specification, and the novel features of the device will beparticularly pointed out in the appended claims.

My invention is illustrated in the accompanying drawing forming a part of this application, in which Figure l is a plan view of a can testing table;

Figure 2 is a side elevation of Figure 1, certain parts being shown in section; and

Figure 3 is a cross section of the vacuum cup used in testing the cans.

A suitable combined feeding and driving means I58 for the can testing table D is shown in Figure 1. A guide rail I53 guides the cans 1, that are to be tested, onto the testing table. The testing table comprises a gear I68 meshing with the gear I58 and driven thereby, and a spacing ring I6I attached to the gear I68 and having pockets I62. 30 The cans enter the pockets I62 and are retained therein by a guard rail I63.

Spaced from the gear I62 and aflixed thereto by bolts I 65 is amounting ring I66 to the lower face of which a number of vacuum testing cups vided with a central hole "I into which a bushing I12 is inserted. The bore of the bushing communicates with a hole I13 of a small diameter arranged in the lower portion of the member-sl68 and communicates with the inside. of the cupshaped member I68. The bushing I12 slidably carries a plunger I15 which normally closes the hole I13. The plunger is loosely received in the bushing so that air .can pass thereby. The plunger I15 has a transverse opening I11 through which an arm I18 ofa lever I19 extends. The. other arm I88 of the lever extends upwardly. The lever I19 is adapted to swing about a shaft NH and the upward movement oi the arm I18 is limited by a stop pin I82. The shaft I6I and the pin I82 are supported by a lever block I83 which is supported on the mounting ring I66.

From the foregoing description of various parts ofthe testing table D, the operation thereof will be readily understood.

Immediately after entering the testing table the cans encounter .an upwardly inclined slide I85 (see Figure 1) with a fiat portion I85. The slide are forced upwardly and against the vacuum cups I68. The latter spread outwardly as shown in Figure 2, and the air confined in the cup is forced 'out through the opening I13 and the bushing.

The passing air exhausting from the cup momentarily lifts the plunger I 15 upwardly, but the atmospheric pressure immediately thereafter forces the plunger downwardly, thereby closing the opening I13 and preventing the passage of air into the cup through the bore of the bushing. Therefore, when the cans leave the'fiat portion I85 of the slide I85 they continue to travel in suspended positions, being so held by the vacuum cups I 68.

The cups I68 are of sufficient size to cover a considerable area of the can top, and if it happens that some vent in the cover has not been properly sealed, then air. from the inside of the can begins to seep into the cup I68. This releases the vacuum and the cup drops the can, which thereafter continues to travel on the gear I68, until it strikes a finger I81, and is thereby directed onto a belt I88. This belt runs between the guards is placed in the path of the cans, whereby the cans I I89 and I98 and delivers the cans to an operator.

Well sealed cans remain in suspended position, and pass over the finger I81, but are dropped down thereafter by means of a release finger I92. This finger is attached to the guard I98 and extends over the ring I66 so that the upstanding arms I88 strike the release finger while corresponding testing cups I61 pass thereunder. The arm I88 being struck by the release finger I92 swings in a. clockwise direction, and by means of the arm I18 raises the plunger I15. Air is thereby allowed to enter the cup I68. The can immediately drops onto the gear I68, and on its further forward movement strikes the deflecting rail I94 and is thereby guided into a discharging chute l95. i

The checking of the filled and sealed cans dispenseswith the old method' of immersing each.

can in water and noting whether any bubbles escape from the sealed portion, and substitutes vacuum cups which support the cans. If a can leaks, the vacuum cup will release it and this can is separated from the others and is delivered back to the inspection table. The good cans are subsequently released from the vacuum cups and are delivered to the discharge chute.

While I have shown only the preferred form of my invention, it should be understood that various changes or modifications may be made within the scope of the appended claims without departing from the spirit of the invention.

I claim:

1. A checking device for filled and centrally sealed cans comprising a moving conveyor for carrying filled cans in an upright position, a plurality of vacuum cups positioned above the cans and movable along with the cans, means for moving the cans into engagement with the cups for causing the cups to contact with the can tops and to enclose the centrally sealed portion, on the top, whereby the cups will continue to support the leakproof cans above the conveyor and faulty cans will drop from their cups onto the conveyor, and means for freeing the leak-proof cans from their cups and for segregating them from the faulty cans.

2. In combination, a conveyor for filled cans, a vacuum cup disposed above each can and being movable with the conveyor, means for raising the cans so that the vacuum cups will contact with the can tops and will enclose the sealed part, said cups carrying the cans from the can raising means and supporting them clear of the conveyor, whereby leaky cans will permit air to enter their vacuum cups and allow these cans to drop onto the conveyor, means for removing the leaky cans from the conveyor, and means for admitting air to the vacuum cups of the good cans for freeing these cans from the cups.

3. In combination, a conveyor for filled cans, a vacuum cup disposed above each can, and being movable with the conveyor, means for raising the cans so that the vacuum cups will contact with the can tops and will inclose the sealed part, said cups carrying the cans from the can raising means and. supporting them clear of the conveyor, whereby leaky cans will permit air to enter their vacuum cups and allow these cans to drop onto the conveyor, means for removing the leaky cans from the conveyor, the good cans being carried beyond said last named means, each vacuum cup having an air vent, means for normally closing said vent, and means for removing said last named means from the vent for admitting air to the vacuum cup of the good can, whereby the good cans are freed from the cups at a point removed from the faulty cans.

, GUY P. HENSLEY. 

